Zigzag-stitching machine



Oct. 3, 1933. R. BECKER ZIGZAG STITGHING MACHINE Filed May 16, 1932 2 Sheets-Sheet 1 Oct. 3, 1933. R. BECKER ZIGZAG STITCHING MACHINE Filed May 16, 1932 2 Sheets-Shea?l 2 'lll/lllllllllll:

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Patented Get. 3, 1933 ziGzAG-srrircmno MAoH'INE' Rudolphecker, North Plainfield, N. J., assigner to The Singer -Manufacturing Company,

Y Elizabeth, N. J., a corlmration'oil NeW'Jersey Amiata@ May 16, 1932:' serai Nh. 611,485

e crains. y(o1. i12-159) This invention relates to sewing machines and more particularly to stitch sewing machines.

One of the objects of this invention is `to pro- V vide improved means for 'adequately support-` ing the seam at'the stitching point in the operation or joining the abutting edgesof the Work.

lWith the above and other objects in view, .as

will hereinafter' appear, the invention consists in l()v the devices, combinations, and arrangementsof parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of'the invention, fromv which kthe several featuresof the' invention and the advantages attained thereby will befreadily understood by those skilled in the art. Y p

In the drawings: Figure 1 is a front `side elevation, partly in section, of a machine embodying my invention. Figure 2 is `a fragmentary plan view' of the sewing machine bed. j Figure 3 is a fragmentary front end elevation of the machine."

Figure 4 is a sectional View of a portion of the machine representing the throat-plates, taken along the line 4 4 of Figure 2.

Figure 5 is a view similar to Figure 4, showing the stitch-forming mechanism and movable throat-plate in a different position.` Figure 6 is a perspective view of a portion of the stationary throat-plate representing the stitch-Enger. This invention is shown as applied to a sewing machine for forming zigzag stitches of the type illustrated .in Patent No. 1,197,735, granted A. Grieb, September 12, 1916. The machine includes the usual bed l, standard 2, and an overhanging bracket-arm 3 terminating in a head 4. Pivotally secured at 5 to the head 4 is a needle-bar frame 6 having iournaled therein a needlebar 7 carrying the eye-pointed needle 8. Clamped upon the needle-bar is a split hub 9 which is pivotally connected'to a short link 10 which lis pivotally secured at 11 to one end of the vibrating arm 12.

12 is fulcrumed at 13 upon the overhanging arm 3 and its other end is operatively connected by the pitrnan--14 with an actuating crank or eccentric l5 on the mainshaft 16.

described connections the needle-bar 7 is reciprocated verticaliy in the swinging needle-bar frame 6.

Journaled in a suitable bearing in the bed 1 is a sleeve 17 which embraces a loop-taker shaft .55 17 having a loop-taker 18 fixed thereto. The

overseaming and zigzag The vibrating armv Through the above.

loop-takershaft 17 is ydriven by the main shaftk 16 ,through the extensible coupling 19. e

From the foregoingit Willbe seen that the needle-,bar land -looper are capable of, bodily movement at right angles to the line of feed. To 60. produce .such movements, adjustable 4actuating mechanism isremployed. Thisactuating mecha- Y nisin'. comprises a rocking flever v20fu1crurned at2l to the standard 2., Thedepending-arm of thev lever v20 -is piv'otally connected at.22.to `65. one end ofthe link 23. Theother en d of the A link'` 23 is `pivotally connected at 2 4 to a lug 25 secured tothe movable sleevefl7-vvhich ernbraces the loop-taker shaft. 17. Secured tothe lug25 by thev screw'25' isanarrow` movable 701 throat-plate 26 having a needle-aperture. 27. To the ,upwardly extending arm of the lever 20 there is pivotally secured by means of the pivot-screw 28 one end of the link 29 having t'SppQSite endlpivotally secured tothe needle-bar frame 75 6 by the pivot-screw 30. To the rockinglever. 20there is pivotally secured by meansY of the stud-f screwv 31, one endof the short link 32l having its opposite end formed with a hub 33 to receive the shouldered adjusting bolt 34 which is received 8i) in the groove in the lever 36, fulcrumed at 37 upon the standard 2. The lever 36 is provided with a depending extension 38 carrying a camfollower 39 fitted within the cam-race 40 of the cam-wheel 4l. wheel 41 is alge'ar 42 meshing with a-gear V43 on the main shaft 16. Through the above 'de" scribed connections lateral motion is transmitted through the aforesaid rocker and link connections to the loop-taker and the Aswinging needle; 90.` bar frame.

The machine is tted withthe usual four-motion feed-dog 44 mounted in the upright portion 45 of Vthe feed-bar 46 which performs the usual oscillating and rising-and-falling movements.

The foregoing description has been directed to a sewing machine of the Wellknown Singer zigzag stitching type, known commercially as the Singer 112 machine. For a more` complete 1,99 description of this type of machine reference may be had tothe Grieb patent previously referred to. Removably and adjustably secured to the bed l by the screw 47 is a stationary throat-plate 48 10'5 having a rearwardly pointing stitch-linger 49, atV the sides of which are needle-apertures 50 through which the needle descends. The stitchfinger is tapered and beveled and rearwardlyy thereof an opening 51 is provided to permit the 1'10 MadeA integral with the cam- ,85V y stitches which are laid under the finger to slip oii of the nger as the work is advanced.

The function of the stitch-finger 49 is to support the seam at the stitching point in the operation of joining the abutting edges 53 (Figs. 4

and 5) of the work, and to prevent the threadsr from distorting the work when the stitches are Seth As shown in Figures 4 and 5, the stitch-finger 49 is thinner than the body of the stationary throat-plate 48 to aord clearance, between the under side of the finger and the reciprocating throat-plate 2'7, for the limbs ofthe needle-loop extending around the looper.A

In the operation of the machine, assuming tlfxe parts to be in the position shown in Figure 4, the stitch to the left of the sttch-nger 49 having been completed and the needle, loop-taker and movable throat-plate 26 having Ybeen shifted laterally of the lineof feed, the needle descends on theright side! of the stitch-finger@- and between the-limbs 52 of' the needle-loop on the loop-taker 18'. The loop-.taker seizesa new loop fromthe needle and passes it throughthe previously formedV needle-loop, the needle ascends and rthe stitch sset. 'When theneedle reaches substantiallyits highest position above the work the needle, loop-taker and movable throat-plate 26`are shifted concomitantly, by the mechanism heretofore described, tothe. position shown in Figure 5. The shifting of the movable throatplate `2S bends' theftwo'l-imbs 52 of the loopextending around the loop-taker under the stitchflnger`49 and positions the limbs 52 of the loop so that the needle will pass between them on its descending movement. f

From the foregoing description considered in connection with the accompanying drawings, the

construction, manner of., operation and severa-lV 4o" advantages of my improved zigzag-stitching machine will beclearly and fully understood. It is apparent that such'a device has a Wide variety of uses, and it will be understood that the form, construction and arrangement of the several elements employed may be varied. Therefore, the privilege is reserved of resorting to all such legitimate changes therein as may be fairly embodied4 within the spirit and scope of the appended claims. r

Having thus set forth thenature Vof theinvention, what I claim hereinV isz- 1. In a sewing machine, in combination, a needle-bar frame mounted for lateral movement, a needle-bar journaled therein, a loop-taker, an axially movable loop-taker shaft and a member adapted to move therewith, a throat-plate carried'bysaid member, a second throat-plate overlying said first mentioned throat-plate, said second mentioned throat-plate having a stitch-nnger with its upper face in the same plane as the upper face of the throat-plate and its lower face spaced from Vsaid rst .mentioned throat-plate.

2. A sewing machine having in combination, a needle', a loop-taker, means for vibrating said needle and loop-taker laterallyof the line of feed, a throat-plate, a stitch-linger carried by said throat-plate, and a movable thread-loop positioning element for bending thread-loops under` said linger, said thread-positioning element being spaced from said stitch-finger to' provideA clearance for the thread-loops. 3. A sewing machine having in combination, a

vreciprocating needle', a loop-taker cooperating therewith, means for vibrating said needle and loop-taker laterally ofthev line of seam formation, a movable throat-plate, aA stationary throatplate overlying said movable throat-plate' and having a stitch-inger and needle-apertures on each side of said stitch-finger, said stitch-finger being thinner than the body of the stationary throat-plateI to provide clearance between thev under side of the` finger and the movable throatplate. 7

' RUDOLPH BECKER. 

